The Brazilian citrus history is marked by several phytosanitary outbreaks due to entry of new pests, frequently with high potential to generate economic losses. Some of these pests have threatened even the viability of citrus in Sao Paulo State, like Huanglongbing (HLB) that was responsible for eradicating 18 million plants between January 2005 and July 2012. This requires development of new methods to control the disease and ensure the economic viability of the activity. This study aimed to analyze costs and benefits of a broad control of HLB in the state (66 % of orchards are inspected and have HLB-symptomatic trees eradicated) and compare this scenario to another one representing a lower level of control (reference scenario, considering that only 26% of orchards manage HLB and proceed the eradication). We chose the Benefit-Cost Analysis to evaluate the differences between scenarios.  Losses caused by HLB comprised a reduction in productivity, elimination of infected plants and increase in production costs (due to inspections, insecticide applications, tree elimination and replanting). Costs and benefits were calculated according to state’s phytosanitary status in 2010. The epidemiological model proposed by Bassanezi & Bassanezi (2008) was used to project the disease progress, crop loss damage, the citrus orchard size, orange production and producers’ costs of production to control the disease over 20 years. The ratio B/C was estimated at 4.07 accumulated for the whole period. This result shows that each R$ 1.00 invested by producers to manage the HLB, prevents them from losing R$ 4.07 in gross revenues.

Bahia is the second most important citrus region in Brazil, accounting for 5.5% of Brazilian production. 80% of this production comes from family based farms, which depend on this crop for economic support. Huanglongbing (HLB) was never recorded in Bahia, but is already spreading in three other citrus-producing states of the country, one of which borders the state of Bahia. Thus, this study aimed to estimate the potential economic impact resulting from an eventual introduction of HLB in Bahia. The mathematical model of Gompertz and a logistic model were used to determine the epidemiological pattern of the disease, considering three scenarios. In scenario A, the efforts of the Bahia State Agency of Agricultural Defense were positive preventing the establishment of HLB (baseline scenario). In scenario B, there was the introduction of the bacteria into Bahia citrus orchards, and the absence of control measures contributed to the expansion of HLB in the following years. In scenario C, after detection of the disease, the producers would adopt control measures: eradication of symptomatic hosts and the insect vector population suppression. The costs of disease control were measured by the need for sprays, carrying out periodic inspections and eradication of plants with symptoms. The net present value (NPV) was used for comparing different scenarios. The results showed that, if HLB is introduced in Bahia, the losses would be very significant in the following 20 years. Should control and eradication procedures not be followed, losses of up to US $ 890,7 million  could occur.